Take three travelers, a nation of Buddhists, and one unfortunate rodent. Add a forbidden journey and a dark childhood secret, and you could have the time of your lives.

The lion-dogs barked all night, lunging and snapping taut their heavy chains, mistaking gusts of wind for intruders. We collapsed our tents in the predawn dark and left the gear on the broken stones of the former temple as the monks had suggested. Slipping back out below a whistling sky, we moved along the wall past piles of stone tablets all engraved with the same hypnotic chant—om mani padme hum, om mani padme hum, om mani padme hum, "hail to the jewel in the lotus"—as if the wind itself were using the tablets as a hymnal.

To stay warm, we simply hiked swiftly. By the time we crossed the Metoktang River it was light enough to switch off our headlamps. We walked through a yak herder's camp where great black beasts snorted columns of white steam. A woman in angular swaths of black was milking one of the yaks. Brigitte went over to speak with her, but the woman fled to her black tent.

It was steep going into a hanging valley, and then level again. Cold squalls kept coming and going. I was making my case for the irrationality of reincarnation and waiting for Brigitte, the scientist, the physicist, to chime in.

"Matter cannot be created or destroyed, only reformed," she said at last. "If you want to infer something spiritual from that—"

"Brigitte!"

"Well, Mark, it's up to you."

Maury was walking ahead of us with his arms crossed and his fedora pulled down over his ears. "We not only come back in a new form," he declared. "I believe we choose the form we come back in."

"What!" This was too much. "Who would ever choose to come back as that dying barefoot child we saw carrying water yesterday morning?"

"I don't know," said Maury, his tone implying not that it couldn't happen, but that he himself didn't have an example.

"C'mon, Maury, this is preposterous. Forget about coming back as a beetle or a rat; just take a child who dies of starvation or AIDS or malaria. Who would choose that life? For that matter, take any kid who is abused by his parents and tell me he chose to be reincarnated into that kind of suffering."

Maury glanced back over his shoulder. "I suppose it depends on the kind of lives, the hundreds or thousand of lives he's lived before."

It was too cold to talk anymore. We finally reached the 17,300-foot pass overlooking Lhamo Latso—"a sharp cragged ridge," according to The Power-Places of Central Tibet, "upon which is built the Dalai Lama's throne, and from this eminence the divine rulers of Tibet once sat to gaze into the lake...to divine the future." The throne itself was buried beneath untold thousands of prayer flags frozen into an icy mound, and the wind was cutting us in two. The sacred lake didn't look any different from a thousand other inhospitable high-altitude tarns found everywhere in Tibet.

Maury and Brigitte and I tried to stay up high and stare down into the oracle-lake because we all want a vision, we all want something mysterious and inexplicable and portentous to happen to us—especially those of us who doubt that such things can happen. We braced ourselves amid the creaking flags and peered down into the hard blue lake until our eyes blurred and our faces froze and our feet began to slip. To me it was just like standing on the summit of a mountain: no divination, no enlightenment, just the howl and bite of cold doing all it could to freeze solid the blood in three beating hearts.